Interesting that Toyota and Hyundai are both introducing hydrogen powered cars in California next year. It seems that the few hydrogen fueling stations are sourcing from natural gas. It is relatively simple to extract hydrogen from water using cheap, simple parts from a hardware store. I mean cheap and simple, like under $20. Of course storing it safely is the trick. I extracted enough to blow a water bottle full of hydrogen across the front yard, rocket style.

I doubt they're gaining energy at all. You always use more energy in the exchange of energy forms than you gain. Second law of thermodynamics? OTH, if you're using clean energy like wind or solar to extract hydrogen, it is a good thing because the only byproduct burning hydrogen is water, pure water at that.

Since you know so much about it Smurf, do youwhat are the issues, if any, with the leftover by products after extracting hydrogen from natural gas? I mean, hey, it can't be good! has to be some bad stuff remaining, like CARBON! OTH, using water leaves us with oxygen. Not bad. Not bad. Besides, water is a lot more plentiful than nat gas. Transportation logics and extraction issues are greatly reduced by sourcing hydrogen from water, right? With nat gas, there is danger on either side of the extraction, whereas with water, the danger is only with the hydrogen.

The problem with extracting H2 from H20 is that it is a very inefficient process. Much better to charge EV batteries directly @95% efficiency if you want to get the most usable energy from your input, IMO.

conklinc wrote:Since you know so much about it Smurf, do youwhat are the issues, if any, with the leftover by products after extracting hydrogen from natural gas? I mean, hey, it can't be good! has to be some bad stuff remaining, like CARBON!

Natural gas, CH4, is comprised mostly of hydrogen and the rest is carbon. So if the hydrogen is being extracted then that sure does leave carbon. I don't know in what form (C, CO, CO2 or something else) the carbon ends up, but it is certainly a by-product.

The real issue is this however.

Suppose that a significant number of cars in California (or anywhere else) start using hydrogen as a fuel. That hydrogen then has to be produced by some means be it from natural gas or from water.

But producing hydrogen from water, is really just producing hydrogen from electricity so far as resource use is concerned. It's the electricity, not the water, which is the primary input of significance (well, it is unless you're in the middle of the desert and have a heap of solar panels that are otherwise unused).

In California as in most places, the "cheap" sources of electricity generation run constantly (or are fully used at other times in the case of hydro) and there is little if any ability to increase output from existing plants. That's hydro, nuclear etc and in most places (not California) coal. So any increase in power generation necessarily comes from the marginal sources of supply - natural gas, oil etc.

So it's really a question of burning gas at a power station versus turning the gas itself into hydrogen. Unless you have a 100% renewable electricity supply, and can increase renewable output so as to produce the hydrogen, hydrogen "from water" is really just a means of turning fossil fuel generated electricity into a flammable gas that can power an engine. Potentially useful if we run short of oil, but it's by no means a "clean" or renewable energy source.

Production of hydrogen from natural gas is roughly 80% efficient. That is, only about 20% of the energy in the natural gas is lost during the conversion. In contrast, generating electricity from gas is 15 - 60% efficient (typically in the mid-30's) and converting that electricity into hydrogen is also quite inefficient.

In short, if we're going to use fossil fuels to generate the electricity then to the extent that we're going to produce hydrogen, it makes far more sense to do it directly from natural gas rather than by means of first turning the fuel into electricity.

For the record, there was a commercial scale electrolysis plant in operation in Hobart from 1956 to the mid-1980's. Originally using 100% hydro-electricity in an era when Australia had no natural gas production, it made a lot of sense back in the 1950's to build it. But the emergence of the Australian natural gas industry (1969) plus the ending of the 100% hydro era in Tasmania doomed the electrolysis plant economically. The last year of full production was 1974 after which it ceased to be financially viable unless the electricity was basically free.

It limped along operating intermittently until finally closing in 1985, with the Hydro essentially giving any surplus power they had to the plant (they were basically just trying to keep people employed in a factory rather than letting the dams spill over). It ran for about 20 weeks in 1975 (a wet year), 10 weeks in 1976 (also quite wet), 5 weeks in 1977, 6 weeks in 1978 and then for a total of about 9 weeks over the following 7 years until final closure in 1985. The only reason it survived at all after 1974 was that it was already built and was running on free power. Once it became necessary to spend money on maintenance, it just wasn't viable to continue and so that was it - game over.

The hydrogen produced at this plant was used to produce fertilizer. It was quite a big operation in its' heyday, with most of the fertilizer being shipped interstate, but it just couldn't compete against production based on natural gas and that's despite the efforts of the power supplier (which did not itself own the plant) to keep it in business.

I don't have a precise figure, but the vast majority of commercial hydrogen production globally is from natural gas. Electrolysis just isn't financially viable, or sensible in terms of resource use, unless you have either a very cheap source of renewable electricity (realistically that would be hydro) and/or don't have access to natural gas.

Smurf, this is fascinating! I'm still digesting what you've written, but a couple of comments off the top of my dunder-head:

I shouldn't think that the relative inefficiency of converting nat gas to electricity (you say typically in the 30ish%) should matter that much, considering present transport technology using an ICE is only about the same % in terms of efficiency. OTH, if hydrogen conversion from water was in the hands of a consumer with solar panels on their roof, and it was sized proportionally, it would be 100% efficient, because it is free energy being used and no pollution is being produced, just pure clean hydrogen energy, with a little water as a byproduct out the tail pipe, and oxygen back into the atmosphere.

Incidently, I read last week in "Solar Industry," a subscription based online Rag out of the U.S., . . . that one solar panel research outfit has managed to squeeze 44% efficiency out of a new panel design. Granted, this was done under "laboratory conditions."

Also, there is much ado about how solar and wind compliment each other, as typically wind generation is most efficient at night, when solar is useless . . . at least photovoltaics is useless. Concentrated solar is making deep inroads towards 24-7 production.

In my estimation, its like the Prof at Uni Melbourne said in his Age article, what differences does it make whether your car is being energized at 8 pm or 3 am? In this case, whether it is during the day using solar to extract hydrogen during the day or wind at night?

The way I see the issue is that the ONLY advantage fossil fuels have is the relative ease to transport them where needed. The disadvantages are that they are dirty and they are not renewable. But unless and until society decides clean air is more important than ease of transport, the renewables are going to struggle. It doesn't help that governments and the fossil fuel industry are fighting the dirty fight, either.

I don't mean to be political here, but independent, verifiable facts prove it. In my home state of Utah there two particular bills being considered for the next session of the legislature in Jan . One involves providing incentives for e-fueling stations, and the other providing nat gas refueling stations. The e-fueling station bill is sponsored by a Democrat, the nat gas fueling station bill is sponsored by a Republican. Does this sound like a familiar refrain to us here in Oz? Same thing going on here now, the current administration is anti-renewable energy.

What to do with the carbon monoxide? It can be used on site as fuel to produce the steam or it can be put through a second reaction as follows

CO + H20 (steam) = CO2 (carbon dioxide) + H2 (hydrogen).

So overall via both steps CH4 (natural gas) and H20 (water in the form of steam) goes in and you get CO2 (carbon dioxide) and 4 H2 (hydrogen) out.

I'm not a chemist, but that's basically how it works. The key point being that the amount of energy required to produce the steam, is relatively small versus the amount that is lost if hydrogen is produced from fossil fuels via the electrolysis route.

Similar things can be done with coal. I'm not sure if the same process was used elsewhere in Australia, but he Launceston Gas Company had a multi-stage production process running until the end of the 1970's as follows.

1. Conventional gas works extracted "town gas" from coal by means of heating the coal in vertical retorts. It's a continuous production process - coal goes in the top and coke comes out the bottom with the gas being driven off and collected. This, or the earlier use of horizontal retorts to achieve the same result, is how town gas was produced. The gas output of this process is a mix of hydrogen gas, methane and carbon monoxide. Main waste products are tar and coke with minor by-products being sulphur compounds.

Step 2 in the process used in Launceston was to take the coke from the first stage (plus locally mined poor quality coal that wasn't good enough to use in the first stage of production) and heat it (via combustion) in the second stage. High temperature steam is then injected, reaction as follows:

C + H20 = CO (carbon monoxide) + H2 (hydrogen).

Step 3 is to crack oil (or the tar left over from step 1) into the gas at high temperature via another reaction. I'm not sure of the exact chemical reaction, but basically it was to take the CO + H2 mix at high temperature and inject (spray) hot oil / tar into the gas stream. The end result is a mix of CO + H2 + HC (hydrocarbons) - all of which are flammable gases.

Step 4 - the gas output of step 1 and step 3 is then combined and exits the plant as "town gas" for cooking, heating, hot water etc.

This plant was operational in that form until roughly 1978 when it was replaced with a catalytic butane cracker on the same site. I'm not sure of the exact reactions which take place, but it's a very similar concept to the natural gas to hydrogen idea. Take the butane (C4H10), add steam at high temperature in the presence of a catalyst, and you end up with a mix of flammable gas outputs. This plant operated until 1997, after which the whole system was closed on account of economic factors. Location of this operation was Launceston Tasmania, just opposite City Park. It's a well known site locally, and some of the old buildings (most notably the vertical retort building) are still there today although the site has partly been redeveloped for non-gas related use.

I know that the other states all had coal gas plants in the past (as in step 1 above) but I'm not sure how far they went with steam reforming and catalytic reactions. At a guess, Victoria probably had the most elaborate operations I'd expect (just guessing).

Another one in Tas - there was a naptha cracking plant in Hobart which operated 1964 - 1978. It's essentially the same process with steam and catalysts to produce a flammable gas product.

Basically, there's about 250 years of research behind all of this changing of hydrocarbons (coal, oil, natural gas) from one thing to another so it's pretty well understood. New Zealand had a natural gas to petrol (actual real petrol as such) production plant running until a few years ago.

So steam is involved! Unless it is generated utilizing renewables, the carbon issue raises its ugly head again. I guess it is for science, chemistry and engineering to figure out the cleanest option here. But bottom line, it appears that hydrogen cars are not going to be free of some sort of pollution sourcing. It would seem that Kurt's i-MiEV recharged on his new solar array is going to be about as clean and efficient as technologically possible. Other than the carbon thrown into the environment during the manufacture of his panels and inverter, he's going to cruise around and about with literally NO carbon footprint.

OTH, scientists have been working on fuel cells producing hydrogen using bacteria to breakdown organic matter for quite sometime now. Perhaps someday . . . The futuristic plan is to have fuel cell stations wherein one merely swaps out the spent fuel cell for a full one. I think Renault wants to do that with the Lithium batteries if I recall the literature correctly.

There are some engineering issues surrounding the use of Hydrogen in vehicles. I took the following quotes from Paul Roberts book "The End of Oil". The book is described as (refer the Wikipedia page): "perhaps the best single book ever produced about our energy economy and its environmental implications." Well worth a read:

- A standard ICE (internal combustion engine) vehicle will last for approximately 150,000 miles, today's fuel cell vehicles struggle to run for longer than 30,000 miles - hardly something that will entice the average buyer;

- Even when compressed, hydrogen remains far less energy dense than gasoline (Oil). A large fuel tank, barely big enough to fit into the trunk of a car, would yield a cruising range of well under two hundred miles, as compared with the three hundred - to four hundred mile range that consumers now expect from standard ICE vehicle;

- Handling and storage of hydrogen is extremely expensive (I believe that it is leaky, picture trying to store water in a slowly leaking sieve!); and

- Fuel cells are expensive to produce and the catalysts are comprised of expensive materials such as platinum.

Plus as you previously mentioned due to the second law of thermodynamics, it take more energy to manufacture hydrogen than you liberate by combusting it. It is a losing game. Fossil fuels still have a positive energy returned on energy invested, but as the easy to extract Oil is depleted and mining moves into more difficult locations such as extreme environments or deep water, this EREOI is falling rapidly. Think about it this way, it takes Oil to extract Oil from deposits. The harder those deposits are to get at, the more energy they take to extract it. It then also takes further Oil to transport that Oil from that distant location to a refinery, storage and then the end consumer.

It is possible that we can get to a situation where there is Oil in the ground, but it is uneconomic to extract it. This is a similar situation to producing hydrogen where it takes more energy to produce it than you obtain from combusting it.

Oil is the backbone of our entire transport infrastructure.

However, I still reckon, if the hydrogen economy could compete economically with an Oil based economy, then we'd be seeing it in action. I'm yet to see a fuel cell or hydrogen powered vehicle on the road with support infrastructure.

It is a fascinating subject. Thanks for raising it.

Hi Smurf,

Thanks for mentioning the town gas plants. Just north of Melbourne in Fitzroy North, there is a large 40 acre park (Edinburgh Gardens) part of which used to be the site of the town gas plant for Melbourne (as well as National Canning Industries site too I think). It is now a mix of housing, public housing and park. When I was younger they still had some of the train tracks, railway bridge and an old steam locomotive in the park. One of the local pubs even used to be called the "Gasometer". It has all been removed now and it is a very well established park (part of it always was a park), but occasionally you can still see some of the old cast iron street lamps which are now no longer functional. Who knows what is below the ground there?